This invention relates to a drawbar connecting together railroad cars, and more particularly to a drawbar arrangement embodying a simplified construction and arrangement of parts that includes a drawbar with a convex spherical end contained between a front draft block support against a wear block by a center sill and a rear support block supported against a gravity-fed wedge by the center sill.
As is known, most prior art railroad coupler assemblies are relatively complicated and include a draft sill, draft gear, yoke, follower block, striker, pin or coupler connection and the coupler itself and its associated components. Such conventional coupler arrangements have a degree of free and cushioned slack. That is, there is a certain amount of free "play" between the coupler components when the load changes from a draft to a buff load, and vice versa. At the same time, the draft gear acts as a spring mechanism to cushion impacts between adjacent cars. Research has indicated that eliminating the free and cushioned slack within a train can eliminate over the road train action forces due to "run-ins" and "run-outs". The magnitudes of these forces are large and cause significant wear and tear on the rolling stock and in some instances are severe enough to cause derailments.
Furthermore, in conventional coupler assemblies, the key or pin connection of the coupler to the yoke is at a relatively long distance from the kingpin about which the wheel truck rotates. In negotiating curves, particularly under buff loading conditions, this gives rise to relatively large lateral forces which can cause derailments. The same is true when jackknifing occurs under buff loads with lateral forces attempting to rotate the cars about their centers.